Divide the full cost of paid time and overheads by realistic billable hours. Include non-billable work and employment costs where applicable. Compare the result with the price you can lawfully charge for the actual support, not an assumed universal NDIS rate.
Use a consistent period
Choose a week or month and keep every input in that period. For a simple weekly model:
Cost per billable hour = ((hourly wage × (1 + on-cost percentage) × paid hours) + weekly overheads) ÷ billable hours.
On-costs in this planning model are your estimate of relevant costs beyond the base wage. Actual award classification, penalties, allowances, leave, superannuation and other obligations need their own current calculation. A single percentage is not a payroll engine.
A fictional small-team example
Assume A$40 base wage, 25% illustrative on-costs, 38 paid hours, 25 billable hours and A$500 allocated weekly overheads.
Loaded wage is A$50 per paid hour. Weekly employment cost is A$1,900. Add A$500 overhead and divide A$2,400 by 25 billable hours: A$96 per billable hour.
At 30 billable hours the same simplified cost becomes A$80. At 20 it becomes A$120. That sensitivity is why utilisation deserves attention.
These figures are invented for learning. They are not actual SCHADS rates, a recommended fee, a price limit or permission to claim non-billable time.
Identify what fills the gap
Paid time can include supervision, training, records, travel, meetings, coordination and gaps between appointments. Decide which costs belong in wages and which belong in overheads, then avoid counting the same cost twice.
A sole trader should still consider the value of their own time, illness and leave coverage, administration and retirement provision. “I do not pay myself a wage” does not make the work economically free.
Distinguish cost, price and claimability
Your cost model describes your business. The relevant pricing and funding arrangements determine what you may charge and claim. Changing your spreadsheet cannot make an unsupported claim valid.
The NDIA requires complete and accurate records of supports delivered. Keep the operational record, permitted pricing and invoice consistent. Check current arrangements for the exact service date and item before billing.
Improve the model without reducing necessary care
Look for avoidable travel, duplicate administration, poor scheduling and software that creates rework. Do not assume the answer is fewer records, inadequate supervision or rushing support.
Test the effect of realistic changes individually. If the service is structurally unaffordable at the applicable price, reconsider the model before accepting obligations you cannot sustain.
Open the billable-hour calculator and replace the fictional assumptions with properly calculated business estimates.
Sources & checking
- NDIA: record keeping requirements · checked 2026-09-23
ProviderQMS editorial guidance and fictional examples. Source checking is not a professional endorsement. Our editorial method.